Activities like yoga, tai chi and meditation are often credited with their spiritual and emotional benefits, but researchers are steadily discovering that they have a range of physical benefits as well. In 2015, for example, it was found that meditation could reduce practitioners' levels of perceived pain by activating and deactivating different parts of the brain. Now researchers out of Coventry University in the UK and Radboud University in the Netherlands have discovered that activities that link body and mind can actually reverse a genetic process that leads to inflammation and disease.

The researchers looked at previous studies that measured the results of activities like yoga and meditation, which are known as mind-body interventions (MBIs). They started with 716 articles and using stringent selection criteria, wound up using 18 studies that featured a total of 846 participants. The studies all included gene-expression analysis as part of the measurements of outcomes.

They found that people who practice MBIs had a decrease in the production of a molecule known as nuclear factor kappa B (NF-kB). This molecule responds to stress by activating genes that produce proteins known as cytokines that cause inflammation in the body. Fewer NF-kb means fewer cytokines. When present in the body over the long term, this pro-inflammatory compounds can increase cancer risks, lead to accelerated aging and even contribute to depression.

"Millions of people around the world already enjoy the health benefits of mind-body interventions like yoga or meditation, but what they perhaps don't realize is that these benefits begin at a molecular level and can change the way our genetic code goes about its business," said lead investigator Ivana Buric. "These activities are leaving what we call a molecular signature in our cells, which reverses the effect that stress or anxiety would have on the body by changing how our genes are expressed. Put simply, MBIs cause the brain to steer our DNA processes along a path which improves our wellbeing."

The researchers add that the release of cytokines triggered by NF-kB could once have been beneficial in humans as part of our occasionally triggered flight-or-flight response to stimuli – in helping to heal wounds, for instance. But now that stress is persistent in many people's lives on a daily basis, excess inflammation is a destructive force, but one that can apparently be countered with MBIs.

"More needs to be done to understand these effects in greater depth, for example how they compare with other healthy interventions like exercise or nutrition," says Buric. "But this is an important foundation to build on to help future researchers explore the benefits of increasingly popular mind-body activities."

The study has been published in the journal Frontiers in Immunology.